GRUB, or GRand Unified Bootloader, is a free and open source bootloader for x86 computers. It is designed to easily allow the booting of multiple operating systems, such as Linux, Windows, or FreeBSD.
How it works[]
GRUB consists of several parts. The first part is a simple bootstrap code that the BIOS finds on the hard drive and launches. This code then loads the next part of GRUB, which scans the hard drive and displays a list of available operating systems. This list is generally found in the /boot/grub directory of the primary Linux/BSD installation, but can also be found elsewhere.
[]
The menu.lst file is the default name for the menu and instructions for booting each operating system at boot. For a typical Linux installation, an entry will look something like:
| title | Linux distro |
| root | (hd0,2) |
| kernel | /boot/vmlinuz-2.6.24-6 acpi=force noapic |
| initrd | /boot/initrd-2.6.24-6 |
| saveddefault |